乳化剂对丙烯酰胺反相微乳液共聚合的影响

Inverse microemulsion copolymerizations of acrylamide(AM) with acrylimide ethyltrimethylammonium chloride(AETMAC) have been carried out in the systems of non ionic emulsifier SPAN 80 and anionic emulsifier sodium di(2 ethyl) hexyl phosphate(DOP), respectively, and the effects of the emulsifiers on the copolymerization rate and reactivity ratio have been investigated. The copolymerization rate was found higher in DOP system and the reactivity ratio of AETMAC was lower in SPAN 80 system than in DOP system and aqueous solution. The results are explained in terms of the difference in tightness of emulsifier layers.

反相微乳液法合成淀粉接枝丙烯酰胺、丙烯酰亚胺乙酯三甲基氯化铵共聚物

以淀粉为基材,通过反相微乳液聚合法与丙烯酰胺、丙烯酰亚胺乙酯三甲基氯化铵进行接枝反应制备共聚物。考察了引发剂种类及用量、乳化剂种类及用量、单体配比、盐类添加剂等因素对单体转化率、接枝率、产物特性粘数的影响。实验结果表明:以过硫酸铵-尿为引发体系,m(Span20)∶m(OP4)=40∶60的混合物为乳化剂,质量分数为7%;正己醇为助乳化剂,质量分数为3%;丙烯酰胺与丙烯酰亚胺乙酯三甲基氯化铵质量比为4∶1,接枝聚合物的接枝率达到127%,特性粘数达到1 060 mL/g。而质量分数为3%的乙酸钠和丙酸钠的加入可使产品特性粘数增加至1 210 mL/g和1 130 mL/g。